ScienceShot

ScienceShot: Planets Orbit Dead Stars

LONG BEACH. CALIFORNIA—Planets appear to be everywhere astronomers look, even in orbit around white dwarf stars—the compacted and slowly cooling "corpses" of stars like our own sun. At the 221st meeting of the American Astronomical Society here, researchers reported the discovery of a planetary system around a white dwarf in the famous Hyades star cluster. This cluster is only 150 light-years from Earth and easily visible to the naked eye on a bright winter night. It's only the second time planets have been found in a cluster similar to the one that probably gave birth to our own sun. It's circumstantial evidence, though: The planets apparently stir up the rocky asteroid belt of the system, and as a result, the white dwarf's outer layers become "polluted" with asteroid dust, which in turn is detectable with sensitive spectroscopes. This may be the ultimate fate of our own solar system, after the sun sheds its gaseous mantle into space and condenses into a white dwarf.